\section{Theory}
Whether a particular grasp is good or not, is ultimately a yes or no answer. Either a hand is able to hold the object, or it is not and the object is dropped. Often one needs to simulate a certain grasp before it is actually executed in a real life scenario, simply to make sure that the grasp is good enough. Usually it is assumed that the object to grasp is a rigid body. This does not need to be the case, as some applications need the objects to be modelled as soft bodies. In the following it will be described what makes up a good grasp of a rigid body.

\subsection{Form \& Force Closure}
When rigid body grasping is considered, form and force closure is often necessary if a grasp is to be successful. Form closure is a kinematic constraint on an object, which immobilizes the object at the contact points between the fingers and the object. Hence if the object is surrounded by contacts, it will be in form closure. Therefore form closure can be seen as a purely geometric property. This means that it is assumed that infinitely large forces and moments can be applied by the hand. In reality a hand would not be able to grasp a object that applies a very large force or torque compared to the power of the motors in the hand. Some fingers would slip, allowing the object to be dropped.\\

\noindent Force closure on the other hand treats each contact as a force, which might include frictional components. These forces will also introduce torques, essentially giving a wrench to the object. It is possible to calculate whether or not a grasp has force closure. By using a wrench space metric it is also possible to quantify how good a grasp is. Force closure takes the limitations of the hand into account in a better way than form closure.
\input{pages/qualitymeasures.tex}
\input{pages/convexhullproj.tex}
\clearpage
\input{pages/robworksim.tex}